Traffic cameras as they are now are probably not the best safety encouragement device. I don't understand why states or localities have not run cameras along major routes and looked for speeding over a longer period of time, as opposed to speeding at a specific point.

It certainly would be a safety device if you were seen traveling effectively +20 mph over 15/20/30 minutes along a highway.. proves a willful negligence to traffic laws while leaving unharmed those that go 15 over to skirt by an 18 wheeler that is fish-tailing.